Creating better health care, education and housing for everyone is a simple idea, but ____ which is hard to put into practice.
Charles Darwin considered ______ to be the process by which evolution took place.
_________, what you did is right. So don’t be worried about it any more.
In our school students are ________ according to how much they know and how old they are.
He is not a(n)________, only a(n) ___________.
The September 11 attack has been _____ by the entire international community.